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Determining drug-drug interactions (DDIs) is an important part of pharmacovigilance and has a vital impact on public health. Compared with drug trials, obtaining DDI information from scientific articles is a faster and lower cost but still a highly credible approach. However, current DDI text extraction methods consider the instances generated from articles to be independent and ignore the potential connections between different instances in the same article or sentence. Effective use of external text data could improve prediction accuracy, but existing methods cannot extract key information from external data accurately and reasonably, resulting in low utilization of external data. In this study, we propose a DDI extraction framework, instance position embedding and key external text for DDI (IK-DDI), which adopts instance position embedding and key external text to extract DDI information. The proposed framework integrates the article-level and sentence-level position information of the instances into the model to strengthen the connections between instances generated from the same article or sentence. Moreover, we introduce a comprehensive similarity-matching method that uses string and word sense similarity to improve the matching accuracy between the target drug and external text. Furthermore, the key sentence search method is used to obtain key information from external data. Therefore, IK-DDI can make full use of the connection between instances and the information contained in external text data to improve the efficiency of DDI extraction. Experimental results show that IK-DDI outperforms existing methods on both macro-averaged and micro-averaged metrics, which suggests our method provides complete framework that can be used to extract relationships between biomedical entities and process external text data.
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Mineração de Dados , Farmacovigilância , Mineração de Dados/métodos , Interações Medicamentosas , Benchmarking , Sistemas de Liberação de MedicamentosRESUMO
BACKGROUND: L-theanine is a unique non-protein amino acid in tea that is widely used as a safe food additive. We investigated the cardioprotective effects and mechanisms of L-theanine in myocardial ischemia-reperfusion injury (MIRI). METHODS: The cardioprotective effects and mechanisms of L-theanine and the role of Janus Kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) signaling were investigated in MIRI mice using measures of cardiac function, oxidative stress, and apoptosis. RESULTS: Administration of L-theanine (10 mg/kg, once daily) suppressed the MIRI-induced increase in infarct size and serum creatine kinase and lactate dehydrogenase levels, as well as MIRI-induced cardiac apoptosis, as evidenced by an increase in Bcl-2 expression and a decrease in Bax/caspase-3 expression. Administration of L-theanine also decreased the levels of parameters reflecting oxidative stress, such as dihydroethidium, malondialdehyde, and nitric oxide, and increased the levels of parameters reflecting anti-oxidation, such as total antioxidant capacity (T-AOC), glutathione (GSH), and superoxide dismutase (SOD) in ischemic heart tissue. Further analysis showed that L-theanine administration suppressed the MIRI-induced decrease of phospho-JAK2 and phospho-STAT3 in ischemic heart tissue. Inhibition of JAK2 by AG490 (5 mg/kg, once daily) abolished the cardioprotective effect of L-theanine, suggesting that the JAK2/STAT3 signaling pathway may play an essential role in mediating the anti-I/R effect of L-theanine. CONCLUSIONS: L-theanine administration suppresses cellular apoptosis and oxidative stress in part via the JAK2/STAT3 signaling pathway, thereby attenuating MIRI-induced cardiac injury. L-theanine could be developed as a potential drug to alleviate cardiac damage in MIRI.
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Apoptose , Glutamatos , Janus Quinase 2 , Traumatismo por Reperfusão Miocárdica , Estresse Oxidativo , Fator de Transcrição STAT3 , Transdução de Sinais , Animais , Janus Quinase 2/metabolismo , Fator de Transcrição STAT3/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Traumatismo por Reperfusão Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/etiologia , Apoptose/efeitos dos fármacos , Glutamatos/farmacologia , Transdução de Sinais/efeitos dos fármacos , Masculino , Camundongos , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêuticoRESUMO
Currently, the emergence of the endemic Coronavirus disease (COVID-19) situation still poses a serious threat to public health. However, it remains elusive about the role of fecal microbiota transplantation in treating COVID-19. We performed a randomized, double-blind, placebo-controlled clinical trial enrolling a cohort of 40 COVID-19 patients with mild-moderate symptoms. Our results showed that fecal microbiota transplantation provided an amelioration in diarrhoea (p = 0.026) of digestive system and depression (p = 0.006) of neuropsychiatric-related symptom in COVID-19 patients, respectively. Meanwhile, we found that the number of patients with diarrhoea decreased from 19 to 0 on day 7 after fecal microbiota transplantation treatment, and it was statistically changed compared to the placebo group (p = 0.047). Of note, the serum concentration of aspartate aminotransferase-to-alanine aminotransferase ratio (AST/ALT, fecal microbiota transplantation, pre vs. post: 0.966 vs. 0.817), a biomarker for predicting long COVID-19, was significantly reduced by fecal microbiota transplantation. In all, our study supports that fecal microbiota transplantation could be a novel therapeutic strategy for COVID-19 patients with diarrhoea and depressive symptoms, which is potentially valuable in ameliorating long COVID-19 symptoms.
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COVID-19 , Depressão , Diarreia , Transplante de Microbiota Fecal , Humanos , Transplante de Microbiota Fecal/métodos , COVID-19/terapia , COVID-19/complicações , Diarreia/terapia , Diarreia/microbiologia , Diarreia/virologia , Masculino , Feminino , Método Duplo-Cego , Pessoa de Meia-Idade , Depressão/terapia , Estudos Prospectivos , Adulto , Idoso , Fezes/microbiologia , Fezes/virologia , SARS-CoV-2 , Resultado do Tratamento , Aspartato Aminotransferases/sangue , Microbioma GastrointestinalRESUMO
Imaging the complex dynamics of micro-vibrations plays a fundamental role in the investigation of microelectromechanical systems (MEMS). However, it remains a challenge for achieving both a wide bandwidth and a low noise due to the high photodetector noise and electromagnetic interference at GHz frequencies. Here, we propose a pulsed laser interferometry system with an adaptable switch to image GHz vibrations based on stroboscopic mixing, while measuring lower-frequency vibrations based on the homodyne scheme. The noise power spectral density is shown in both regions from DC to 10â GHz with an average noise down to 30.8 fm/âHz at GHz frequencies, which holds the highest resolution to the best of our knowledge. Vibrational amplitude and phase mappings of a kHz comb-drive resonator, a GHz piezoelectric transducer, and a GHz film bulk acoustic resonator are presented with animated visualizations and k-space analysis, paving a new paradigm for the first time to image and analyze various MEMS devices of a bandwidth spanning 10 orders of magnitude.
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Clay minerals are ubiquitous in subsurface environments and have long been recognized as having a limited or negligible impact on the fate of arsenic (As) due to their negatively charged surfaces. Here, we demonstrate the significant role of kaolinite (Kln), a pervasive clay mineral, in enhancing As(V) immobilization during ferrous iron (Fe(II)) oxidation at near-neutral pH. Our results showed that Fe(II) oxidation alone was not capable of immobilizing As(V) at relatively low Fe/As molar ratios (≤2) due to the generation of Fe(III)-As(V) nanocolloids that could still migrate easily as truly dissolved As did. In the presence of kaolinite, dissolved As(V) was significantly immobilized on the kaolinite surfaces via forming Kln-Fe(III)-As(V) ternary precipitates, which had large sizes (at micrometer levels) to reduce the As mobility. The kaolinite-induced heterogeneous pathways for As(V) immobilization involved Fe(II) adsorption, heterogeneous oxidation of adsorbed Fe(II), and finally heterogeneous nucleation/precipitation of Fe(III)-As(V) phases on the edge surfaces of kaolinite. The surface precipitates were mixtures of amorphous basic Fe(III)-arsenate and As-rich hydrous ferric oxide. Our findings provide new insights into the role of clay minerals in As transformation, which is significant for the fate of As in natural and engineered systems.
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Arseniatos , Caulim , Oxirredução , Caulim/química , Arseniatos/química , Ferro/química , Compostos Ferrosos/química , AdsorçãoRESUMO
With the widespread use of organophosphate esters (OPEs), the accumulation and toxicity effect of OPEs in biota are attracting more and more concern. In order to clarify the mechanism of toxicity of OPEs to organisms, this study reviewed the OPEs toxicity and systematically identified the mechanism of OPEs toxicity under the framework of adverse outcome pathway (AOP). OPEs were divided into three groups (alkyl-OPEs, aryl-OPEs, and halogenated-OPEs) and biota was divided into aquatic organism and mammals. The results showed that tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) and triphenyl phosphate (TPHP) mainly caused neurotoxicity, reproductive, and hepatotoxicity in different mechanisms. According to the constructed AOP network, the toxicity mechanism of OPEs on aquatic organisms and mammals is different, which is mainly attributed to the different biological metabolic systems of aquatic organisms and mammals. Interestingly, our results indicate that the toxicity effect of the three kinds of OPEs on aquatic organisms is different, while there was no obvious difference in the mechanism of toxicity of OPEs on mammals. This study provides a theoretical basis for OPEs risk assessment in the future.
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Rotas de Resultados Adversos , Retardadores de Chama , Animais , Monitoramento Ambiental , Retardadores de Chama/toxicidade , Retardadores de Chama/análise , Organofosfatos/toxicidade , Ésteres/toxicidade , Ésteres/metabolismo , Mamíferos/metabolismo , ChinaRESUMO
Exposure routes are important for health risk assessment of chemical risks. The application of physiologically based toxicokinetic (PBTK) models to predict concentrations in vivo can determine the effects of harmful substances and tissue accumulation on the premise of saving experimental costs. In this study, Tri(2-chloroethyl) phosphate (TCEP), an organophosphate ester (OPE), was used as an example to study the PBTK model of mice exposed to different exposure doses by multiple routes. Different routes of exposure (gavage and intradermal injection) can cause differences in the concentration of chemicals in the organs. TCEP that enters the body through the mouth is mainly concentrated in the gastrointestinal tract and liver. However, the concentrations of chemicals that enter the skin into the mice are higher in skin, rest of body, and blood. In addition, TCEP was absorbed and accumulated very rapidly in mice, within half an hour after a single exposure. We have successfully established a mouse PBTK model of the TCEP accounting for multiple exposure Routes and obtained a series of kinetic parameters. The model includes blood, liver, kidney, stomach, intestine, skin, and rest of body compartments. Oral and dermal exposure route was considered for PBTK model. The PBTK model established in this study has a good predictive ability. More than 70% of the predicted values deviated from the measured values by less than 5-fold. In addition, we extrapolated the model to humans. A human PBTK model is built. We performed a health risk assessment for world populations based on human PBTK model. The risk of TCEP in dust is greater through mouth than through skin. The risk of TCEP in food of Chinese population is greater than dust.
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Fosfatos , Fosfinas , Pele , Camundongos , Humanos , Animais , Toxicocinética , Poeira , Modelos BiológicosRESUMO
Electrodes are indispensable components in semiconductor devices, and now are mainly made from metals, which are convenient for use but not ideal for emerging technologies such as bioelectronics, flexible electronics, or transparent electronics. Here the methodology of fabricating novel electrodes for semiconductor devices using organic semiconductors (OSCs) is proposed and demonstrated. It is shown that polymer semiconductors can be heavily p- or n-doped to achieve sufficiently high conductivity for electrodes. In contrast with metals, the doped OSC films (DOSCFs) are solution-processable, mechanically flexible, and have interesting optoelectronic properties. By integrating the DOSCFs with semiconductors through van der Waals contacts different kinds of semiconductor devices can be constructed. Importantly, these devices exhibit higher performance than their counterparts with metal electrodes, and/or excellent mechanical or optical properties that are unavailable in metal-electrode devices, suggesting the superiority of DOSCF electrodes. Given the existing large amount of OSCs, the established methodology can provide abundant electrode choices to meet the demand of various emerging devices.
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Histone deacetylase (HDAC) 1, a member of the histone deacetylases family, plays a pivotal role in various tumors. In this study, we collected 7313 human HDAC1 inhibitors with bioactivities to form a dataset. Then, the dataset was divided into a training set and a test set using two splitting methods: (1) Kohonen's self-organizing map and (2) random splitting. The molecular structures were represented by MACCS fingerprints, RDKit fingerprints, topological torsions fingerprints and ECFP4 fingerprints. A total of 80 classification models were built by using five machine learning methods, including decision tree (DT), random forest, support vector machine, eXtreme Gradient Boosting and deep neural network. Model 15A_2 built by the XGBoost algorithm based on ECFP4 fingerprints showed the best performance, with an accuracy of 88.08% and an MCC value of 0.76 on the test set. Finally, we clustered the 7313 HDAC1 inhibitors into 31 subsets, and the substructural features in each subset were investigated. Moreover, using DT algorithm we analyzed the structure-activity relationship of HDAC1 inhibitors. It may conclude that some substructures have a significant effect on high activity, such as N-(2-amino-phenyl)-benzamide, benzimidazole, AR-42 analogues, hydroxamic acid with a middle chain alkyl and 4-aryl imidazole with a midchain of alkyl whose α carbon is chiral.
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Algoritmos , Aprendizado de Máquina , Humanos , Relação Estrutura-Atividade , Estrutura Molecular , Máquina de Vetores de Suporte , Histona Desacetilase 1RESUMO
The pursuit of high metal utilization in heterogeneous catalysis has triggered the burgeoning interest of various atomically dispersed catalysts. Our aim in this review is to assess key recent findings in the synthesis, characterization, structure-property relationship and computational studies of dual-atom catalysts (DACs), which cover the full spectrum of applications in thermocatalysis, electrocatalysis and photocatalysis. In particular, combination of qualitative and quantitative characterization with cooperation with DFT insights, synergies and superiorities of DACs compare to counterparts, high-throughput catalyst exploration and screening with machine-learning algorithms are highlighted. Undoubtably, it would be wise to expect more fascinating developments in the field of DACs as tunable catalysts.
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Catalysts made of in situ exsolved metal nanoparticles often demonstrate promising activity and high stability in many applications. However, the traditional approach is limited by perovskites as prevailing precursor and requires high temperature typically above 900 K. Here, with the guidance of theoretical calculation, an unprecedented and substantially facile technique is demonstrated for Cu nanoparticles exsolved from interstitially Cu cations doped nickel-based hydroxide, which is accomplished swiftly at room temperature and results in metal nanoparticles with a quasi-uniform size of 4 nm, delivering an exceptional CO faradaic efficiency of 95.6% for the electrochemical reduction of CO2 with a notable durability. This design principle is further proven to be generally applicable to other metals and foregrounded for guiding the development of advanced catalytic materials.
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At present, there is a general contradiction between permeability and selectivity of reverse osmosis (RO) membranes for desalination; a membrane with higher water permeability will give a lower salt rejection or selectivity, and vice versa. In this work, single-layer nanoporous graphene is used as RO membrane to investigate the effects of pore shape to reduce this contradiction by molecular dynamics simulations. Two kinds of pores (round and rectangular pores) with different sizes are simulated. For round pore, although the water permeability increases with the increase of the pore size, the salt rejection rate drops rapidly. For rectangular pore, reasonable designed pore structure can achieve improved water permeability and high salt rejection of graphene membrane by keeping one-dimensional length (i.e. the width) of the pore less than the size of the hydrated ions and increasing the other dimensional length. The restriction of one dimension can prevent the passage of hydrated ions through the pore effectively. This 'one-dimensional restriction' provides a simple strategy for designing RO membrane with variable pore structures to obtain a better desalination performance.
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BACKGROUND: Congenital myasthenic syndrome (CMS) is a heterogeneous group of rare disorders with impaired neuromuscular transmission caused by genetic defects, which is characterized by fatigable muscle weakness. CASE PRESENTATION: Herein, we report a case of limb-girdle CMS (LG-CMS) in a 15-year-old Chinese girl with limb weakness and mild ptosis. The patient presented with well-defined clinical manifestations, muscle imaging, and electrophysiological features associated with CMS. On muscle biopsy, in addition to tubular aggregates identified, an extremely unusual pathological change of rimmed vacuoles in muscle fibers was observed. Whole-exome sequencing disclosed two novel heterozygous variants (c.14 T>A and c.581 T>C) in the human glutamine-fructose-6-phosphate transaminase 1 (GFPT1) gene, leading to the substitutions of phenylalanine to tyrosine (p.F5Y) and serine (p.F194S), respectively. Both variants were predicted to be likely pathogenic by SIFT, Polyphen-2, and Mutation Taster. Treatments with pyridostigmine bromide and albuterol produced a dramatic improvement. CONCLUSIONS: Collectively, molecular genetic analysis and muscle biopsy play crucial roles in the diagnosis of GFPT1-related LG-CMS with rimmed vacuoles (a rare phenotype of CMS) and have important implications for treatment decision.
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Síndromes Miastênicas Congênitas , Adolescente , Feminino , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Humanos , Fibras Musculares Esqueléticas , Mutação/genética , Síndromes Miastênicas Congênitas/genética , VacúolosRESUMO
The sudden outbreak of COVID-19 has led beach tourism to a complete halt in January 2020, disrupting millions of livelihoods and businesses. Due to the economic importance of beach tourism, many governments reopened tourist beaches after the number of confirmed cases decreased. It is essential to open beaches orderly to meet the needs of tourists, maintain beach's health and restore coastal economy under the new reality. This paper selected Qingdao in China as a case study, drew on a questionnaire survey among beach tourists, summarized the effects of the COVID-19 on beach tourism industry and tourism enterprise, analyzed beach tourists' psychology and behavior, and developed beach management strategy under the ongoing prevention and control of COVID-19. The results showed that the COVID-19 pandemic caused severe damage to beach tourism which bases on travel and mobility, and this industry was temporarily suspended. With the changing epidemic situation, beach tourism witnessed a gradual recovery from stagnation to local tourism. Meanwhile, tourism enterprises were hit by the devastating impact of the COVID-19, causing problems such as business reduction, tense cash flow, high operating cost and unclear market prospect. Under the normalization of pandemic prevention, tourists did not have severe fear and anxiety about the pandemic, and placed great importance on the prevention and control measures, emergency measures and pandemic risk level of the beach destination. The pandemic also reshaped the perception and mode of beach tourism. Ecological tourism, travelling with family, and local tourism became the primary choices for tourists. Beach congestion, health status, and the quality of tourism services were the biggest concerns for tourists. Additionally, social media and short video APP became the new marketing channels. Finally, beach management strategies were proposed from the aspects of pandemic prevention and control, emergency management, information communication, tourist management, service management, and environmental management.
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Separation of Xe and Kr is one of the greatest challenges in the gas industries owing to their close molecular structure and similar properties. Energy-effective adsorption-based separation using chemically stable carbon adsorbents is a promising technology. We propose a strategy for Xe/Kr separation using MOF-derived metallic carbon adsorbents. M-Gallate (M=Ni, Co) were used as precursors to fabricate CoNi alloy nanoparticles embedded carbon adsorbents by one-step auto-reduction pyrolysis. The optimal NiCo@C-700 exhibits record-high IAST selectivity (24.1) and Henry's selectivity (20.1) of Xe/Kr among reported carbon adsorbents. DFT calculations, local density of states calculation, charge density difference, and Bader charge analysis reveal the great affinity with Xe benefits from the presence of Ni or CoNi nanoparticles as a result of more charge transfer from Xe than Kr to metal, thus providing higher binding energy. Breakthrough experiments further verify NiCo@C-700 a promising candidate for Xe/Kr separation.
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BACKGROUND: Environmental stress is a crucial factor restricting plant growth as well as crop productivity, thus influencing the agricultural sustainability. Biochar addition is proposed as an effective management to improve crop performance. However, there were few studies focused on the effect of biochar addition on crop growth and productivity under interactive effect of abiotic stress (e.g., drought and salinity). This study was conducted with a pot experiment to investigate the interaction effects of drought and salinity stress on soybean yield, leaf gaseous exchange and water use efficiency (WUE) under biochar addition. RESULTS: Drought and salinity stress significantly depressed soybean phenology (e.g. flowering time) and all the leaf gas exchange parameters, but had inconsistent effects on soybean root growth and WUE at leaf and yield levels. Salinity stress significantly decreased photosynthetic rate, stomatal conductance, intercellular CO2 concentration and transpiration rate by 20.7, 26.3, 10.5 and 27.2%, respectively. Lower biomass production and grain yield were probably due to the restrained photosynthesis under drought and salinity stress. Biochar addition significantly enhanced soybean grain yield by 3.1-14.8%. Drought stress and biochar addition significantly increased WUE-yield by 27.5 and 15.6%, respectively, while salinity stress significantly decreased WUE-yield by 24.2%. Drought and salinity stress showed some negative interactions on soybean productivity and leaf gaseous exchange. But biochar addition alleviate the negative effects on soybean productivity and water use efficiency under drought and salinity stress. CONCLUSIONS: The results of the present study indicated that drought and salinity stress could significantly depress soybean growth and productivity. There exist interactive effects of drought and salinity stress on soybean productivity and water use efficiency, while we could employ biochar to alleviate the negative effects. We should consider the interactive effects of different abiotic restriction factors on crop growth thus for sustainable agriculture in the future.
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Carvão Vegetal , Secas , Glycine max/efeitos dos fármacos , Glycine max/crescimento & desenvolvimento , Biomassa , Gases/metabolismo , Folhas de Planta/metabolismo , Estresse Salino , Glycine max/metabolismo , Água/metabolismoRESUMO
BACKGROUND: It is well demonstrated that immunosuppressants can reduce, but not eliminate the risk of generalized development in ocular myasthenia gravis (OMG). In this study, we aimed to explore the predictive factors of generalized conversion of OMG patients who received immunosuppressive treatments. METHODS: OMG patients under immunosuppressive treatments in Tangdu Hospital from June 2008 to June 2012 were retrospectively reviewed. Baseline clinical characteristics were documented. Patients were followed up regularly by face-to-face interview and the main outcome measure was generalized conversion. The logistic regression analysis was performed to determine the predictive factors of generalization of OMG. RESULTS: Two hundred twenty-three eligible OMG patients completed the final follow-up visit and 38 (17.0%) progressed to generalized MG (GMG) at a median time to generalization of 0.9 year. Patients with adult onset and positive repetitive nerve stimulation (RNS) of facial or axillary nerve had higher conversion rate than those with juvenile onset and negative RNS (p = 0.001; p = 0.019; p = 0.015, respectively). Adult-onset patients converted earlier than juvenile-onset OMG patients (p = 0.014). Upon multivariate logistic regression analysis, age of onset (Odds ratio [OR] 1.023, 95% confidence interval [CI] 1.006-1.041, p = 0.007) and positive facial nerve RNS (OR 2.826, 95%CI 1.045-5.460, p = 0.038) were found to be positively associated with generalized development. Moreover, an obviously negative association was found for disease duration (OR 0.603, 95%CI 0.365-0.850, p = 0.019). CONCLUSIONS: Age of onset, disease duration and facial nerve RNS test can predict generalized conversion of OMG under immunosuppressive therapy. Adult-onset, shorter disease duration and facial nerve RNS-positive OMG patients have a higher risk of generalized development.
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Progressão da Doença , Imunossupressores/uso terapêutico , Miastenia Gravis/tratamento farmacológico , Miastenia Gravis/patologia , Adulto , Idade de Início , Criança , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/fisiopatologia , Razão de Chances , Estudos Retrospectivos , Fatores de RiscoRESUMO
Chemical oxidation using peracetic acid (PAA) can be enhanced by activation with the formation of reactive species such as organic radicals (R-Oâ¢) and HOâ¢. Thermal activation is an alternative way for PAA activation, which was first applied to degrade micropollutants in this study. PAA is easily decomposed by heat via both radical and nonradical pathways. Our experimental results suggest that a series of reactive species including R-Oâ¢, HOâ¢, and 1O2 can be produced through the thermal decomposition of PAA. Sulfamethoxazole (SMX), a typical sulfa drug, can be effectively removed by the thermoactivated PAA process under conditions of neutral pH. R-O⢠including CH3C(O)O⢠and CH3C(O)OO⢠has been shown to play a primary role in the degradation of SMX followed by direct PAA oxidation in the thermoactivated PAA process. Both higher temperature (60 °C) and higher PAA dose benefit SMX degradation, while coexisting H2O2 inhibits SMX degradation in the thermoactivated PAA process. With a variation of solution pH, conditions near a neutral value show the best performance of this process in SMX degradation. Based on the identified intermediates, transformation of SMX was proposed to undergo oxidation of the amine group and oxidative coupling reactions. This study definitively illustrates the PAA decomposition pathways at high temperature in aquatic solution and addresses the possibility of the thermoactivated PAA process for contaminant destruction, demonstrating this process to be a feasible advanced oxidation process.
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Sulfametoxazol , Poluentes Químicos da Água , Peróxido de Hidrogênio , Oxirredução , Ácido PeracéticoRESUMO
A reliable electrochemical biosensor is reported based on nitrogen-doped graphene nanosheets and gold nanoparticle (Au/N-G) nanocomposites for the event-specific detection of GM maize MIR162. The differential pulse voltammetry response of methylene blue (MB) was chosen to monitor the target DNA hybridization event. Under the optimum conditions, the peak current increased linearly with the logarithm of the concentration of DNA in the range 1.0 × 10-14 to 1.0 × 10-8 M, and the detection limit was 2.52 × 10-15 M (S/N = 3). It is also demonstrated that the DNA biosensor has high selectivity, good stability, and fabrication reproducibility. The biosensor has been effectively applied to detect MIR162 in real samples, showing its potential as an effective tool for GM crop analysis. These results will contribute to the development of new portable transgenic detection systems. Graphical abstract .
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DNA/química , Técnicas Eletroquímicas/métodos , Grafite/química , Nanopartículas Metálicas/química , Nitrogênio/química , Zea mays/químicaRESUMO
BACKGROUND: Alzheimer's disease (AD) is a prevalent form of dementia leading to memory loss, reduced cognitive and linguistic abilities, and decreased self-care. Current AD treatments aim to relieve symptoms and slow disease progression, but a cure is elusive due to limited understanding of the underlying disease mechanisms. MAIN CONTENT: Stem cell technology has the potential to revolutionize AD research. With the ability to self-renew and differentiate into various cell types, stem cells are valuable tools for disease modeling, drug screening, and cell therapy. Recent advances have broadened our understanding beyond the deposition of amyloidß (Aß) or tau proteins in AD to encompass risk genes, immune system disorders, and neuron-glia mis-communication, relying heavily on stem cell-derived disease models. These stem cell-based models (e.g., organoids and microfluidic chips) simulate in vivo pathological processes with extraordinary spatial and temporal resolution. Stem cell technologies have the potential to alleviate AD pathology through various pathways, including immunomodulation, replacement of damaged neurons, and neurotrophic support. In recent years, transplantation of glial cells like oligodendrocytes and the infusion of exosomes have become hot research topics. CONCLUSION: Although stem cell-based models and therapies for AD face several challenges, such as extended culture time and low differentiation efficiency, they still show considerable potential for AD treatment and are likely to become preferred tools for AD research.